Method of Preparing Stable Oxide Ceramic Precursor Sol-Gel Solutions Based on Lead, Titanium, Zirconium and Lanthanide(s) and Method of Preparing Said Ceramic

A method of preparing a stable sol-gel solution as precursor of an oxide ceramic based on lead, titanium, zirconium and a lanthanide metal, the method comprising in succession the following steps:

• a) preparing a sol-gel solution by bringing a lead-containing molecular precursor, a titanium-containing molecular precursor, a zirconium-containing molecular precursor and a lanthanide-metal-containing molecular precursor into contact with a medium comprising a diol solvent and optionally an aliphatic monoalcohol;
• b) leaving the sol-gel solution obtained in step a) to stand for a sufficient time needed to obtain a solution having an approximately constant viscosity;
• and
• c) diluting the sol-gel solution obtained in step b) to a predetermined amount with a diol solvent identical to that of step a) or a solvent miscible with the diol solvent used in step a).

A method of preparing an oxide ceramic material comprising lead, titanium, zirconium and a lanthanide metal, the method comprising at least one cycle of steps including, in succession:

• a) depositing a layer of a sol-gel solution on at least one of the faces of a substrate, said sol-gel solution being obtained by the method comprising:
• i) preparing a sol-gel solution by bringing a lead-containing molecular precursor, a titanium-containing molecular precursor, a zirconium-containing molecular precursor and a lanthanide-metal-containing molecular precursor into contact with a medium comprising a diol solvent and optionally an aliphatic monoalcohol;
• ii) leaving the sol-gel solution obtained in step i) to stand for a sufficient time needed to obtain a solution having an approximately constant viscosity;
• and
• iii) diluting the sol-gel solution obtained in step ii) to a predetermined amount with a diol solvent identical to that of step i) or a solvent miscible with the diol solvent used in step i);
• and
• b) heat treating said layer and converting said layer into the oxide ceramic.